The outside middle area of my chest hurts a lot when i strech or touch the middle of it?What should I do

In brief:
Stretching

Stretching or touching an area near your chest and having it hurt could be
1.

Muscular ie from doing an activity in excess such as a push=up
2. Related to the joint where the breast bone or sternum meet the ribs a common source of pain
3. Related to something in a rib or muscles such as a fracture or trauma or bruising
4. Related to a heart or lung issue
if it is purely tender to touch and hurts more with stretching it is more comonly1, 2 or 3.
But number 4 is still possible
without more information it is too general a question to leave alone and you should call your doctor.

In brief:
Stretching

Stretching or touching an area near your chest and having it hurt could be
1.

Muscular ie from doing an activity in excess such as a push=up
2. Related to the joint where the breast bone or sternum meet the ribs a common source of pain
3. Related to something in a rib or muscles such as a fracture or trauma or bruising
4. Related to a heart or lung issue
if it is purely tender to touch and hurts more with stretching it is more comonly1, 2 or 3.
But number 4 is still possible
without more information it is too general a question to leave alone and you should call your doctor.
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